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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

21577 results found.

  1. GRB000926 - Optical observations
  2. GRB000911: VLT infrared observation
  3. GRB000926 - Optical observations
  4. GRB000926 - Optical observations
  5. GRB 000926: optical observations
  6. GRB 000926, Optical Observations
  7. GRB000926 - Optical observations
  8. GRB000911: optical VLT observations
  9. GRB000926 K'-band Observation
  10. GRB000926 optical observations
  11. GRB000926 - Optical observations
  12. J and K band observations of GRB 000926
  13. GRB000911 Optical Observations
  14. GRB 000926, optical observation by Oksanen (vsnet-grb)
  15. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  16. GRB000926: Optical observations
  17. GRB 000926 HST/Chandra TOO Status
  18. GRB000926, radio observations
  19. GRB 000926: Optical candidate
  20. IPN triangulation of GRB000926
  21. GRB000911: Sub-millimeter observations
  22. IPN triangulation of GRB000925
  23. GRB000911, Radio and Optical observations
  24. GRB000911, Radio observations
  25. GRB000911: Optical observations
  26. IPN triangulation of GRB000911
  27. IPN triangulation of GRB000910
  28. GRB 000830: Optical observations
  29. GRB000830: Optical observations
  30. GRB000830, TNG B-band observations
  31. GRB000830: Optical observations
  32. GRB000210, Optical observations
  33. "Snapshot" afterglow IDs and GRB 000830
  34. GRB000830: Optical observations
  35. IPN triangulation of GRB000830
  36. HST/STIS observations of the host galaxy of GRB 980329
  37. HST/STIS observations of the chaotic environment of GRB 980613
  38. IPN localization of GRB000820
  39. SGR 1806-20 burst activity
  40. GRB000812, TNG R-band observations
  41. GRB000801 & GRB000730, Gamma Ray Observations
  42. GRB000730, Gamma Ray Observations
  43. GRB000812, Radio observations
  44. IPN localization of GRB000812
  45. IPN localization of GRB000811
  46. GRB000801, Gamma Ray Observations
  47. GRB000801, VLT-Antu R-band observations
  48. GRB000301C, UBVI optical observations
  49. GRB000801, Radio Observations
  50. Updated IPN coordinates for GRB000801
  51. IPN localization of GRB000801
  52. IPN localization of GRB000730B
  53. IPN localization of GRB000730B
  54. IPN localization of GRB000730
  55. GRB 990510: Possible detection of a host galaxy
  56. GRB 000727, optical observations
  57. IPN localization of GRB000727
  58. GRB 990705, HST/STIS observations of the host galaxy
  59. GRB 990712: Late time HST/STIS Observations
  60. GRB 991216, HST/STIS observations
  61. GRB000620, Radio Observations
  62. GRB981226, HST/STIS observations of the host galaxy
  63. GRB000630, optical observations
  64. GRB 000630: Detection of the Optical Afterglow
  65. GRB000630, Optical Observations
  66. GRB000630, optical observations
  67. GRB000630, optical observations
  68. GRB000630, optical observations
  69. GRB000630, optical observations
  70. GRB000630: Optical observations
  71. GRB000630, Radio Observations
  72. possible optical counterpart of GRB 000630
  73. IPN triangulation of GRB000630
  74. GRB 000623, optical observations
  75. GRB 000620, optical observations
  76. GRB000418, HST/STIS Observations
  77. GRB990123: Late-time HST/STIS observations of the host
  78. GRB 990506, HST/STIS Observations of the Host Galaxy
  79. GRB000623
  80. GRB 000620: J-band observations
  81. GRB000620, optical observations
  82. GRB000615: H-band observations
  83. GRB990308, HST/STIS observations of the host galaxy
  84. GRB000620 - Optical observations
  85. GRB000620 Optical observations
  86. GRB000615, Radio observations
  87. GRB000607, optical observations
  88. GRB 000615: NIR further observations
  89. GRB990123, HST/STIS observations of the host galaxy
  90. GRB000616 optical observations
  91. GRB 000615, near-infrared observations
  92. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  93. GRB000616 [IPN Position]
  94. GRB000615B [IPN Position]
  95. GRB000615, further R-band photometry
  96. GRB 000615: NIR observations
  97. GRB000615, R-band photometry
  98. GRB980425, HST/STIS observations of the host galaxy
  99. GRB 000301C: Further Late-Time HST/STIS observations
  100. GRB980519, HST/STIS observations of the host galaxy

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